RIO DE JANEIRO, BRAZIL – The maxim that “the difference between medicine and poison lies in the dose” has rarely been far from reality. A new confirmation in this sense comes from research conducted by scientists from the Institute of Chemistry (IQ) of Unesp in Araraquara, São Paulo, who have identified in the venom of the Brazilian snake Jararacuçu a peptide (protein piece) that can stop the reproduction of the new coronavirus.
To reach this conclusion, the researchers performed a laboratory analysis that showed the contact between the molecule extracted from the reptile venom and the cells of monkeys contaminated with the virus. The conclusion was that the substance’s effect reduced the virus’s ability to replicate by 75%.
Confirmation of the discovery was published last week in the international journal Molecules in a preliminary study.
“We have found a peptide that is not toxic to cells but inhibits viral replication. If the compound becomes a drug in the future, the organism would have time to act and produce the necessary antibodies, since the virus would be impaired in its speed of infection and would not spread in the organism,” explained Eduardo Maffud Cilli, IQ professor and one of the authors of the paper.
SNAKE PEPTIDES
The protein found in Jararacuçu is a molecule that interacts with and blocks PLPro, one of the enzymes of the coronavirus responsible for its proliferation in cells. This enzyme is common to all variants of the coronavirus, a factor that ensures the effectiveness of the method against various mutations of the virus.
According to Unesp’s press office, the idea to study the potential of the snake’s venom arose when scientists at Unesp’s Chemistry Institute recently discovered that the snake’s peptide has an antibacterial effect, which prompted them to conduct new tests to see if it could also act on viral particles.
The effect was not so high in the first analysis, but after some changes in the chemical structure of the synthesized molecule, the antiviral capacity increased to 75% reproductive blockade.
In the next steps of the study, experts will evaluate the efficiency of different doses of the molecule and whether it can perform other functions in the cell, such as protective functions that prevent the virus from entering the cell.
Once these tests are complete, the research will move into the preclinical phase, where the peptide’s effectiveness in treating animals infected with the new coronavirus will be evaluated.
“Our results are promising and represent a valuable resource in the exploration of new molecules for the discovery and development of drugs against coronavirus infections,” Cilli says.